It is often necessary to provide protection to relatively sensitive circuits used to drive a load in, for example, high voltage applications. The load in such a system may suffer a voltage breakdown that results in a rapid change in voltage across the drive circuits of the load. Such a rapid change in voltage causes damage to components in the drive circuitry.
Our published applications GB-A-2356752 and GB-A-2356753 relate, respectively, to a low impedance power supply for a magnetron, and to a transmission line trigger arrangement for switching modules. It is desirable to protect the modulator switches in a system such as that described from any potentially damaging rapid voltage changes that may occur should the magnetron fail.